The present invention relates generally to analog to digital converters, and more particularly to all optical analog to digital converters.
It is often desirable to convert an analog amplitude varying signal to a digital set of values which corresponds to various voltages in the analog waveform to generate a corresponding digital signal. Conventional approaches generally rely on iterative and/or comparative techniques for determining a digital signal based on an analog waveform voltage. In particular, a common conventional approach compares the actual voltage of the analog amplitude varying signal to a comparison voltage which is generated from a digital word. Various digital words are utilized to create comparison voltages which are then rapidly compared to the actual voltage to determine whether the comparison voltages are greater or less than, in an instant of time, the analog amplitude varying signal. Through a continuous iterative and/or comparative process, a digital word which corresponds to the actual voltage of the analog amplitude varying signal is generated. The digital word is recorded for that instant of time and the same iterative and/or comparative process is repeated for subsequent instants of time corresponding to the analog signal. This conventional method suffers from various shortcomings, including but not limited to, errors and time inefficiency due to the iterative process.
What is needed therefore is an apparatus and method for converting an analog signal into a digital signal which is automatic, accurate, time efficient and does not rely on iterative techniques.